Moving to standard tariff energy rates could cost consumers an extra £136 a year

The big energy companies will switch exisiting customers on to standard tariff rates if they don't act before the end of August

Failing to shop around for better energy deals could cost consumers an extra £136.59 a year when eight fixed dual fuel tariffs expire this month. British Gas, EDF Energy, npower, Sainsbury's Energy and Flow Energy will all switch exisiting customers on to standard tariff rates if they don't act before the end of August.

The average increase on annual bills will be 7.1 per cent (£77.13), but households in the East Midlands on the EDF Energy Blue +Price Promise August 2015 tariff will be hit with a huge £136.59 (13.62 per cent) rise.

Those looking for a new tariff should consider First Utility's new fixed rate deal, offered in conjunction with consumer collective The Big Deal, which uses the bargaining power of tens of thousands of people to save the group money.

A typical household will pay £885 per year for dual fuel on the First Utility tariff, £270 less than the average Big Six standard variable tariff. The deal is fixed until 31 October 2016.

To sign up, visit thebigdeal.com before 26 August and enter your details. You will then be shown how much you could save on the First Utility deal and how it compares to every other deal on the market.